Comments on: Red Hat / CentOS IPv6 Network Configuration

By: Calum

Calum — Wed, 02 Nov 2011 23:24:44 +0000

George – how about cp /etc/sysconfig/network-scripts/ifcfg-lo /etc/sysconfig/network-scripts/ifcfg-eth0
?

By: George

George — Mon, 17 Oct 2011 00:35:01 +0000

Hi I dont find /etc/sysconfig/network-scripts/ifcfg-eth0, I only have /etc/sysconfig/network-scripts/ifcfg-lo…….what can I do ? Help me please

By: Iain Kay

Iain Kay — Fri, 22 Jul 2011 09:26:58 +0000

I have a question. If one has setup a CentOS server, and it is now in production sitting online in use 24/7 with IPv4, is it possible to add IPv6 to it without having to restart the network service?

What I have tried:
$ modprobe ipv6
$ ifconfig eth0 && ifconfig xenbr0

By this point there are no ipv6 addresses shown in ifconfig

$ ip addr add 2001:xx:xx:xx:1::2/64 dev xenbr0

By this point I still have no ipv6 addresses in ifconfig, all I get is:
RTNETLINK answers: Operation not supported

If I absolutely have to reboot the server then I will find a good point to do so and do it but if it’s even remotely possible to do without then that would be ideal. The server hosts Xen virtual machines using bridged networking configuration and somehow I doubt that restarting the network service would play nice with them and come back automatically at Virtual Machine level.

By: Monster

Monster — Fri, 10 Jun 2011 00:12:22 +0000

any idea how to configure IPv6 in bridge for RH based OS?

By: Joel Snyder

Joel Snyder — Sun, 27 Feb 2011 23:16:17 +0000

ipv6.google.com doesn’t resolve today, so it’s a bad example. Try http://www.v6.facebook.com.

By: tomas

tomas — Tue, 16 Nov 2010 20:11:12 +0000

Just a question. How can I calculate usable hosts address? I have assigned IPv6 /48 network and need single adress for each server, for example
3x IPv6 address for server-1
2x IPv6 address for server-2
etc …

By: S!FE

S!FE — Wed, 20 Oct 2010 19:35:17 +0000

I think that works for me, thanks Mr Vivek.

By: Vivek Gite

Vivek Gite — Wed, 20 Oct 2010 15:03:03 +0000

Try

 chkconfig network on

By: S!FE

S!FE — Wed, 20 Oct 2010 13:22:38 +0000

Is there any directive to make network service start at boot time.

By: Pete

Pete — Thu, 07 Oct 2010 18:11:48 +0000

Use IPV6ADDR_SECONDARIES in ifcfg-eth0. Generally, v6 devices expect to have multiple addresses. If you do an ifconfig on eth0, you’ll probably see at least two v6 addresses already (one a link-local scope and one a global scope).

IPV6ADDR_SECONDARIES=”[/] …” (optional)
A list of secondary IPv6 addresses (e.g. useful for virtual hosting)
Example:
IPV6ADDR_SECONDARIES=”3ffe:ffff:0:1::10 3ffe:ffff:0:2::11/128″

By: SH

SH — Thu, 07 Oct 2010 11:27:51 +0000

I try to add another interface (ifcfg-eth0:1) with the same IPv6 lines as in ifcfg-eth0, but the IPv6 does not appear when I use ifconfig. How can I assign an IPv6 to another network interface?

By: Steve

Steve — Mon, 27 Sep 2010 10:41:30 +0000

So how would one find out there IPV6 address to use as a static one and what the default gw IPV6 address us to use?

I know the IPV4 addresses > how do i find its IPV6?

Thanks in advance

By: Pete

Pete — Thu, 15 Jul 2010 16:02:25 +0000

Nice reminders, but I’d like to make two suggestions:

1. Since the gateways are not specific to an interface, I keep the default gateway stuff (v4 and v6) in /etc/sysconfig/network.

2. I also don’t like the v6 autoconf for servers, so I turn it off in /etc/sysconfig/network: IPV6_AUTOCONF=no

Thanks for the quick tips.

Pete

By: Beau

Beau — Tue, 13 Jul 2010 19:26:46 +0000

Thanks so much for this article. It is exactly what I have been looking for. I will recommend this article. Keep up the good work.

By: Sean

Sean — Tue, 15 Jun 2010 18:41:47 +0000

you have no ipv6 mask :(